Abstract/Project Summary Femoroacetabular impingement (FAI) is a morphological deformation of the hip joint that reduces hip range of motion, function, etc. and results in increased pain and disability. The FAI pathology consists of three various sub-types: cam, pincer and mixed (cam & pincer), with the cam-type being present in approximately 48% of those with radiographic signs of FAI. Symptomatic FAI patients usually undergo hip arthroscopy in order to surgically correct for these morphological deformations. In this study, the hip joint cartilage health and joint function of symptomatic cam-type FAI patients that will undergo hip arthroscopy will be assessed over a six month time period. The patients recruited in this study will undergo a unilateral hip MRI of the affected limb as well as undergo functional assessment (self-reported outcomes and physical performance) both prior to and at 6 months after hip femoroplasty, a form of hip arthroscopy used to treat cam-type FAI. The main outcome of this project (Aim 1) is to assess hip joint articular cartilage health (T1? and T2 relaxation times) using a novel voxel based relaxometry (VBR) method. The VBR method has been previously established for use in the knee joint and the applicant will seek to establish a VBR method for use in the hip joint. It is hypothesized that after hip arthroscopy hip cartilage T1? and T2 relaxation times will be altered compared to the baseline (pre- surgery) relaxation times. Aim 2 of the study (secondary outcomes) will assess functional performance and self-reported outcomes of pain, disability and determine the possible associations between these measures with the VBR based assessment of T1? and T2 relaxation times. Functional performance will be assessed using the timed up and go (TUG) and the six minute walk test (6MWT), while self-reported outcomes of pain, physical activity, disability, etc. will be assessed using the HOOS, Harris Hip surveys and the IPAQ. It is hypothesized that patients will demonstrate improved functional performance and self-reported levels of pain, physical activity and disability. In order to accomplish the goals of this study and supplement the candidate?s knowledge base, the candidate will enroll in three courses at the University of California (UCSF) to obtain knowledge in image-based processing. These courses are Image Processing I&II and Musculoskeletal Imaging and will provide the candidate with the knowledge and skills necessary in developing various image analysis applications that will be necessary in achieving the goals of this project. In addition to these courses, the candidate will take advantage of the educational and professional resources (i.e. grant writing workshops, biweekly group meetings/image review, etc.) that are organized and provided by UCSF. Also, the Musculoskeletal Quantitative Imaging Research (MQIR) group, the group that the applicant currently works in, hosts bi-weekly image review and group meetings in which the applicant will be exposed to various clinical and analytical interpretations and applications of musculoskeletal imaging. The physical resources, intellectual and institutional support available at UCSF and within the MQIR group will not only provide an excellent environment for the candidate to succeed in accomplishing the goals of this study but will provide the candidate with the initial steps in obtaining a tenure-track faculty position. The results of this study will help researchers and clinicians to better understand the effects of hip arthroscopy on hip joint health and function as well as support the mission statement of the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS). Also, the knowledge obtained from the results of this study will help orthopaedic surgeons to better understand and improve upon current methods used in hip arthroscopy.